Heat pump



D@.113,1949 M. M. SMHTH ETAL m wg HEAT PIMP I Filed Dec. 2 1946 2Sheets-Sheet l RECEIVER INVENTORS MARVIN M. SMITH MORY N. KEMLEI'R BY QM29% ATTORNEYS Dec. 33, 11949 M S r 2,4,9

HEAT PUMP Filed Dec. 2, 1946 2 She'ets-Shet 2 HEAT EXGHANGER 3 INVENTORSMARVIN M. SMITH ATTORNEYS EMORY N. KEMLER Patented Dec. 13, 1949 HEATPUMP Marvin M. Smith, Munele, Ind., and Emory N.

Kemler, Birmingham, Ala., assignors to Muncie Gear Works, Inc., Munclc,Ind., a corporation oi Indiana Application December 2, 1946, Serial No.713,504

Claims. 1

This invention relates to heat pumps, and particularly to improvementsin deep well devices for utilizing subterranean temperatures as a sourceof heat. Reference is here made to the copending application of MarvinM. Smith, Serial No. 624,351, filed October 25, 1945, with respect towhich the present invention embodies specific improvements.

The main object of the present invention is to provide improved meansfor utilizing deep well water as a source of heat in a heat pump andprevent a condition in which the water standing in the well tends toapproach the temperature of the water in a closed circulatory system soclosely that heat-transfer to or from the closed system is retarded; andto provide improved means whereby, under certain conditions, waterstanding in the well is withdrawn so that its pressure head is reducedand water from around the well flows in.

A further object of the invention is to provide means for automaticallydischarging water from the well to waste when such water has acquired atemperature near that of equilibrium with the temperature of thecirculatory system of the heat pump.

Certain specific embodiments of this invention are illustrated in theaccompanying drawings in which:

Fig. 1 is a diagrammatic representation of a heat pump with closedconduit for circulating a heat conveying medium to and from a deep wellaccording to the present invention.

Fig. 2 is a fragmentary diagrammatic view of a modified form of thesame.

Fig. 3 is a fragmentary diagram of a further modification of the same.

In the form shown in Fig. 1, the heat pump comprises the usualreversible refrigeration cycle apparatus including a compressor l, apair of heat-exchangers serving in the heating season as condenser 2 andevaporator 3, a receiver 4 and expansion valve 5 connected in a closedsystem for circulating a refrigerant. The condenser 2 and evaporator 3may be coils carrying the refrigerant and coupled in heat-exchangerelation with coils 6 and 1, respectively, forming part of a conduit forcirculating a heat conveying medium in a closed circuit with a loop ofpiping 8 that is submerged in a deep well 9 communicating with a sourceof subterranean water whose normal surface level, below the surface itof the earth, is indicated at H.

The upward or out-going lead l2 of the loop 8 is connected to a pump l3which in turn is connected by a three-way valve It with a pipe I!leading to the coil 6 and with a pipe l6 leading to the coil I. Thecoils 6 and I are connected by pipes l1 and I8 to the return lead I! ofthe loop 8. The position of the lever 20 of the three-way valvedetermines the direction of flow of water from the pipe l2 to the pipel5 or l6 respectively.

As is usual in the use of heat pumps for heating or cooling a space, airto be heated is directed over the condenser coil 2 during the heatingseason, as indicated in the diagram by the arrow 21; and during coolingseason, the air current is directed over the evaporator coil 3, asindicated by the arrow 22 in Fig. 1.

During the heating season, the water in the deep well serves as a sourceof heat which is supplied to the evaporator coil 3 through pipes 42 andI6, coil I, and pipes l8 and i9, when the circulating pump l3 andrefrigeration cycle apparatus are in operation, as for example,to heatair exposed to the condenser.

During the pooling season, the deep well serves as a dump for heatdelivered to the circulating medium by the condenser after beingextracted from the air by the evaporator of the heat pump. In suchoperation, the coil 6 absorbs the heat from the condenser coil 2 and theconduit carries it to the well 9 through pipes II and H, the circulatingmedium being cooled in the well, and is returned by pipe l2, pump l3 andpipe IE to the coil 6 in a closed circuit of flow. In the apparatusshown, the three-way valve I4 controls the circulation of thisheat-conducting medium to render the coil 1 operative and the coil 6inoperative during the heatin season, in one position of the handle orarm 20; and another position of said handle 20 renders the coil 6cperative and the coil 1 inoperative in the conduction of the heatingmedium.

In the form shown in Fig. 1, the operation of the deep well as a heatexchanger for either heating or cooling the circulating medium in theloop 8 is intensified by circulating the water of the well.

To this end a pipe 23 extends from a point in the well below the normalground water level to a pump 24, thence through pipe 25 to a tubularcasing 26 which surrounds the return lead it of the loop 8 anddelivers'the contents of said casing close to the bottom of the well. Abranch pipe 21 leads from the pump-24 to waste. The discharge throughthis waste pipe is controlled by a 3 valve 28 which is normally closedbut may be opened by a solenoid which in turn is controlled by athermostat 30 preferably located near the well so as to be sensitive tochanges in temperature in the water; of the well as reflected by thetemperature in the pipe 12.

The thermostat 30 operates-a suitable relay H which closes the normallyopen switch 32 to supply current to the solenoid 28 from line conductors33 and 34. The switch element 35 controlled by the thermostat 30controls the operation oi the relay 3|, as will be understood from theelectrical connections, as diagrammatically indicated in Fig. l.

Inasmuch as the present invention relates mainly to the use of the deepwell as a heat exchanger acting between the subterranean earthtemperature and the temperature of one or the other of the heatexchangers of the refrigeration cycle of the heat pump, it is thought tobe suil'icient for the disclosure of the present invention to confinethe drawings and description to such parts of the heat pump apparatus asare directly involved in the function and operation of the deep wellequipment. Suitable apparatus for reversibly operating the refrigerationcycle is more fully described in Patent No. 2,401,890, issued to MuncieGear Works, Inc. as assignee of Smith, Fields and Kemler.

The operation of the device shown in Fig. l is as follows:

When the heat pump is operating for heating the air of a building, theair flow will be directed over the condenser coils 2, as indicated bythe arrow 2i and the evaporator coil will be isolated from such air flowby its closed housing indicated at 36, the lever 20 will be thrown intothe position in which it is shown in full lines in Fig. l, so that theconduit which carries the circulating heatconducting medium to and fromthe deep well mitted to the refrigerant flowing in coil 3 oftheevaporator., The temperature of this heat is intensified through theaction of the compressor and utilized in the condenser for the heatingfunction. a

In the normal operation of the heat pump. during the heating season, thetime period of continuous operation is relatively short and seldom is itso prolonged that the temperature of the standing water in the wellreaches a point where the water or other circulating'medium passingthrough the loop 8 fails to pick up an 'eilfective quantity of heat fromthe well forproper operation of the heat pump. Such a condition ofequilibrium might be wasteful of power or might be titherwisedetrimental.

'In periods between intervals ofoperation, both the fluid in the closedsystem and that in the well bore have a chance to closely. approach theearth temperature. However, in long periods of operation which occur inextremely cold weather con.- ditions, usually experienced only a fewtimes during the heating season, the operation of the heat pump may bealmost continuous. Under these conditions, thefluid in the well will nothave a chance to store up suillcient heat for the most eflicientoperation of the heat pump.

In order to prevent the occurrence oi such undesirable operatingconditions, the present invention provides means for automaticallydischarging some or the well water to waste so as to cause a freshsupply of water to flow from the earth reservoir into the well bore toreplace that discharged to waste. The fluid brought in by this actionwill be at earth temperature and will assure a proper temperature in thewell bore to cause it to function properly as a source of heat in itsheat exchange relation to the circulating medium.

When in the heating season the circulating water temperature reaches apredetermined low value for which the thermostat 30 has been set toclose the switch 35, this will cause relay 3! to close its switch 32 andactuate the solenoid 2! to open valve 28, so as to discharge water towaste through pipe 21. The valve 28 being normally urged to a closedposition will cut off this waste i when the temperature within the pipel2 has risen suiliciently to permit the thermostat 30 to open its switch35. v

During the cooling season when the deep well is serving as a dump forthe heat that is extracted from the air by the refrigerating cycle, thenthe adjustments of the thermostat 30 are the reverse of those used inthe heating season and are such that the thermostat-causes a dischargeof well water to waste when a certain high temperature exists in theheat-conveying circulating system and cuts oil the discharge to wastewhen a certain lower temperature exists in the circulating system aswill be understood. In such case the tendency of the operation of theheat pump would be to raise the temperature of the v The motor of pump39 is controlled by an elec-' trical relay circuit actuated bythermostat 30, similar to the circuit that controls the waste valve 28of the device of Fig. l.

In the form shown in Fig. 3 the waste pipe ll is directly connected tothe water circulating system connecting the heat exchanger 42 to thedeep well 9. The water thus wasted is replaced in this circulatorysystem by providing a low pressure relief valve 43 at some point in theloop I that is well below the ground water level ii. The waste valve 28and its thermostatically con trolled electric circuit and solenoid, asshown, are the same as those of Fig. 1.

"The embodiments of the invention thatar shown in Figs. 1 and 2 areappropriate for use in climates where it is advantageous to use acirculating fluid in the closed conduit system that will a not freeze;whereas, the comparatively simpler form of Fig. 3 is suitable for usewhere temperature ranges are such that water from the well may serve asthis circulating medium'.

Although several embodiments are herein shown and described. it will heunderstood that numerous details of the invention may be modi "lied oromitted without departing from the spirit We claim:

1. A heat pump, comprising a deep well communicating with a surroundingsource of subterranean water, conduit means for recirculating a heatexchange medium in a closed circuit having a portion thereof submergedin said well, means for discharging standing water from said well, andthermostatic means actuated by temperature changes in said conduit tocontrol said discharge means.

2. A heat pump, comprising a deep well communicating with a surroundingsource of subterranean water, conduit means for recirculating a heatexchange medium in a closed circuit having a portion thereof submergedin said well, a system of piping and a pump for circulating the standingwater of said well in heat exchange relation to said conduit means, awaste pipe connected to said system of piping for discharging standingwater from said well, a valve controlling said waste pipe. andthermostatic means actuated by temperature changes in conduit to controlsaid valve.

3. A heat pump, comprising refrigerant cycle apparatus including a heatexchanger, a deep well communicating with a surrounding source ofsubterranean water, closed conduit means adapted for continuouslyrecirculating water in heat exchanging relation to both said heatexchanger and said well, means for discharging standing water from saidwell, and thermostatically controlled means actuated by temperaturechanges in said conduit to control said discharge means.

4. In a heat pump, comprising refrigerant cycle apparatus including aheat exchanger, a

deep well communicating with a surrounding source of subterranean water,and closed conduit means adapted for continuously recirculating water inheat exchanging relation to both said heat exchanger and said well,means for withdrawing standing water from said well, a discharge pipecommunicating with the last named means, and thermostatically controlledmeans responsive to temperature changes in said conduit means arrangedto control said discharge pipe.

5. In a heat pump, comprising refrigerant cycle apparatus including aheat exchanger, a deep well communicating with a surrounding source ofsubterranean water, and closed conduit means adapted for continuouslyrecirculating water in heat. exchanging relation to both said heatexchanger and said well, means for withdrawing standing water from saidwell, thermostatic control means reponsive to temperature changes insaid conduit means, and discharge means actuated by said thermostaticcontrol means and arranged to govern the operation of said means forwithdrawing water from said well.

'MARVIN M. SMITH.

EMORY N. KEMLER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name I Date 987,475 Martin Mar. 21, 19111,875,305 Hill Aug. 30, 1932 2,109,926 Nelson Mar. 1, 1938

